1. Field of the Invention
The present invention relates to the analysis of social correlation in social networks.
2. Background
Social networking services and systems exist on the World Wide Web that are intended to build online social networks for communities of people having common interests and/or activities, or who are interested in exploring the interests and activities of others. Such systems provide various ways for users to interact, including blogging, discussion groups, email, file sharing, instant messaging, online chat, video, voice chat, etc. Social networking systems such as MySpace.com™ and Facebook™ enable users to create self-description pages (also referred to as a “profile page”), and enable the users to link their pages with pages of friends.
In many such online social systems, social ties between users play an important role in dictating their behavior. One of the ways this can happen is through social influence. According to social influence, the actions of a user can induce his/her friends to behave in a similar way. In social systems where social influence may be exerted, ideas, modes of behavior, new technologies, and/or further concepts can be diffused through the social network by the users. As such, understanding how social influence is manifested within a social network may be leveraged by entities that desire to market products and services to users in the social network.
However, detecting social influence in a social network is a difficult task because it is difficult to distinguish the effects of social influence from other factors that may be present. Examples of such other factors include homophily, where individuals tend to befriend others who are similar to them and thus perform similar actions, or further unobserved confounding variables that can induce a statistical correlation between the actions of friends in a social network. Distinguishing social influence from such factors is similar to the problem of distinguishing correlation from causality, which is a notoriously difficult statistical problem.